Sharpening of endless knife bands



July 17, 1962 w. HOEPE ETAL SHARPENING OF ENDLESS KNIFE BANDS 3 Sheets-Sheet 1 Filed Nov. 5, 1958 INVENTORS ATTORNEYJ July 17, 1962 w. HOPPE ETAL SHARPENING OF ENDLESS KNIFE BANDS Filed Nov. 5, 1958 3 Sheets-Sheet 2 WILL /A M HOPP l A WPENCZ" W s C HOPP ATTORNYS I n INVENTORS '00 E July 17, 1962 w. HOPPE ETAL SHARPENING OF ENDLESS KNIFE BANDS 3 Sheets-Sheet 3 Filed Nov. 5, 1958 INVENTOR5 WILL/AM HOPPE AWRNC w. sum/was:

BY 6.4 8* W141 ATTORNEYS by a parallel linkage blades 10.

ha'san outwardly extending pin '26 which is pivotally re- 'ceived by the lower end of a link 28, the link 28 being maintained on the pin 26.;by a locking'collar 30. Theupper end of the link 28 is-pivotally mounted on a'stud' 32 arrangement which includes are provided for rotating the bone 19 an incremental amounteach time the lever '53 is oscillated. These means (FIGS. 3, 4, and 5) include a ratchet wheel 76 I direction from its rest position of FIG. 3, the pawl 80 extending from a block 34 and maintained thereon by a locking collar 36. The block 34 is secured, as by set screws, to a fixed cross shaft 38 whichlis secured at each end to the side frames 11 as by the illustrated mounting pads 42. V V e 1 1 At this point, note will'be taken of the fact that in the following description reference will be made to several locking or retaining collars such as the collars 30 and 36:

Each of these collars is secured to the pin or stud on which it ismounted by a set screw or the like without specific reference being made to such fasteners'as 'thedescription' proceeds. a

The left hand end of the shaft 22 (FIG. 3) is rotatably received by a block '44 and is axially positioned thereon by a snap ring 46 and a locking collar 48. vThe block 44 has an outwardly extending pin 50 which is pivotally received by the lower end of a link 52 (see also FIG. 2) with a locking collar 53. holding the link 52in place. The

upper end of link 52 is pivotally mounted on a pin54 which extends from a' fixed block 56 and is maintained thereon by locking collars 55 at each end. The block 56, 1

, like the block 34, is also secured'to the cross shaft 38 as by the illustrated set screws.

1 .The center distances (FIG. 3) between the 32 and 26 and 54 and 50 are equal and likewise the center distances between the pins 54 and'32 and-50 and 2 6 are also equal, thus defining aparallel linkage for moving the hone 19 into and out of sharpening engagement with the 7 blades 10. Such movement of the hone 19 may be readily obtained by oscillating one of the short links (52 or 28') of the described parallel linkage. 7 a This endmay be advantageously attained by means of ;-a removable handle or lever 58 (FIGS. Z'and 3) which is slotted at 60 (FIG. 3) to pass over fixed pins 62 and 64 projecting from the link 52 as well as the pin 54'. It

. will also be noted that collars 66 on the pins 62 and 64, V as well as the collar 55; are spaced from the link 52 (FIG.

2) aidistance slightly greater than the thickness of the handle 58 to facilitate its being positioned to swing the hone 19 into and out of sharpening engagement with the workman may sharpen the blades while standing beside the slicing 'IIlQfihiBC-l o I V V e -Refer ring back to the fixed cross shaft 38 (FIG. 3)

it. will be seen that a further block. 68 is secured thereto with a spring pin 70 extending therefrom and angled forwardly of the hone 19 (see also FIG. 4). One end of a ,tensionspring 7 2'is secured to'the pin 70 while its other end is caught by a' spring pin 74 th'readedinto the collar .30jand also serving as a set screw for the collar 30. The

spring 72 urges the hone 19 toward the left'to a position limited by-contact ofthe shaft 22 with the side frame 11 wherein the bone is out of contact with the blades 10 and in a rest positiom, From the above description, it-has' been brought out that the cylindrical hone 19 is brought into and out of Qsharpening engagement with the moving blades 10. Es-

sentially there is'line contact between the blades 10 and "the hone 19 which. is advantageousfor reasons later developed in greater detail. In order that; the hone 19 'does not becomeflatted and this line contact lost means detail, a panel member extends swings downwardly and an inturned lip 82 thereof engages. one of the teeth on ratchet wheel 76 as can be best appreciated from FIGS. 4 and 5 wherein the link 28 has been swung to an extreme counterclockwise position. The hone 19 is thus rotated ina clockwise direction (FIG. 4) each time the handle 58 is swung 'to in a counterclockwise direction as limited by engagement of the shaft 22 with the right hand side frame 11 (FIG. 5). In this manner the peripheral surface of the hone 19 is successively brought into sharpening or honing contact with the blades 10 thus maintaining, or tending to maintain at all times a'srnooth, cylindrical sharpening surface.

In passing, it will be noted that the shaft 22 is axially fixed relative to the block 24 by the ratchet wheel hub 78 anda snap ring 79. A keeper spring 84 is secured to the block 24 by screw 86 and is provided with an in turned lip 88 (FIG. 4 which engages successive teeth of the ratchet wheel 76. In this manner reverse or counterclockwise (FIG. 4) rotation of the ratchet wheel is prevented when the link 28 swings in a clockwise (FIG. 5) direction back to the rest position illustrated in FIG. 3 audio so doingdrags the pawl upwardly over the teeth of Wheel 76. The keeperspring 84 also serves to prevent the hone'19 from being rotated-by the blades 10. That is, when the hone 19 is brought into engagement with the moving blades 10 (FIG. 2) there is a force or drag tending to rotate the hone in a counterclockwise direction. Such counterclockwise rotationis, however, prevented bythe keeper 84.

The lower sharpening unit is similar in construction to the upper unit 19 just described. The principal difference between the two is in the provisions made for disposing the honing member 20 inside of the loops of the endless band knives 10 to sharpen the opposite side of each cutting edge. Referring now to FIGS. 2 and 6 and particularlythe latter, the hone 20 is compositely formed by a plurality of abrading stones 20 held fast on a shaft 105 by. nuts 103. The hone20 is supported from a cross shaft 90 secured at each end to the slicing machine frames 11 as by mounting pads 89. Blocks 91 and 92 are secured to the shaft 90 adjacent the side frames 11 by the illustrated set screws.'- Brackets 93 (see also FIG. 2) and 94 are secured as by welding, to the blocks 91 and 92 respectively and extend upwardly therefrom to receive pins 95 and 96 which in turn pivotally support the bossed upper ends of links 98 and 100. One end of each of the'pins 95 and 96 has an enlarged head portion engaged with the links 98 and 100 with the other ends of the pins 95 and 96 being held in place by lock collars 97 (FIG. 2). Blocks 102 and 104 r'otatably receive the ends of the shaft 105, of the hone 20 and integral pins 106 and 108. extend rearwardly from these blocks and are pivotally received by the links 98 and 100. Lock collars 107 retain the pins 106 and 108 in place on the links 98 and 100. 1

A tie rod 109 is pivotally connected at one end to the link 100 by a pin 110 and at the other endto a small connecting link 112 by a pin 111 (FIG. 6). 'One end of an actuating'link 114 is also pivotally disposed on the pin 111 intermediate the rod 109 and line 112. The pin 111 is headed on one end and held in place by a lock not 113' (FIG. 2) threaded onto its other end. The other 114 (FIG. 6). An operating lever or handle 116 is slotted as at 117 to receive the pins 119 and a fixed pin 118 projecting from the link 114 and is held in place on the link 114 by collars 113' and 12-1 spaced therefrom. The pin 119, it will be seen, provides a fulcrum about which link 114 is rotated by handle 116.

The center spacing between the pins 95 and 106 (FIG. 6) is equal to the center spacing between the pins 96 and 108 and the center spacing between the pins 95 and 96 is equal to that between the pins 106 and 108. This defines a parallel linkage which may be actuated by the lever 116 to carry the hone 20 into parallel engagement with all the knife bands 10. At this point note will be taken of the fact that the hone shaft 105 is axially fixed with respect to the left hand block 102 by means of a snap ring 123 and the hub of a pawl 126, while the right hand end of the shaft 105 is not axially fixed with respect to the block 104. This arrangement is for purposes later discussed. However, the described parallel relationship is at least substantially at all times maintained by the link 112 and the connecting rod 109 and the angular relationships thereof with the links 98 and 100.

The hone 20 is rotated about its axis in essentially the same fashion as the hone 19 to provide for even wear of the cylindrical hone surface. A pawl 124 is secured on the link 98 (FIGS. 2 and 6) and is engageable with ratchet wheel 126 secured to the hone shaft 105. Each time the hone 20 is moved to its left hand position (FIG. 6) a lip 125 (FIG. 2) on the free end of pawl 124 is swung down Wardly into engagement with one of the teeth on ratchet wheel 126 thereby rotating the shaft 105 to bring successive portions of the stones 20' into sharpening relation with the bands 10. A keeper spring 127 is secured to the block 102 by a screw 129 and extends into engagement with the teeth of the ratchet 126 preventing its reverse rotation by the pawl 124 or the moving blades 10.

The hone 20 is normally maintained in the rest position shown in FIG. 6 by a coil spring 128 which is secured at one end to the outer end of link 100 and at its other end to an arm 130' projecting from a collar 131 secured to shaft 90. The spring 128, it will be seen, functions to return the hone 20 to its normal or rest posiiton, disengaged from the bands 10, whenever the handle 116 is released by the operator. Thus also, there is at all times a forcetending to bring the hone 20 out of engagement with the bands 10, thereby minimizing the possibility of the operator maintaining the hone in engagement with the blades long enough to remove an excessive amount of metal from the bands.

For efiicient operation of slicing machines of the type herein referred to, continuous operation with a minimum of down time is essential. Not only does the sharpening apparatus of the present invention minimize or eliminate down time for the sharpening operation, but also provision is made for facilitating replacement of the bands 10. Such provision is required by reason of the preferred mounting of the hone within the loops formed by the knife bands 10 with the cross connection, i.e. the link 112 and rod 109, between the links 98 and 100 disposed outside of the knife band loops. The hone 20 is therefore disassociable from its parallel linkage mounting- Thus it will be seen that one end of the shaft 105 is received by an upwardly open journal formed in the block 102. The block 102 is slotted intermediate its length to receive a retaining spring 135 which is secured in place by a screw 133 with its free, curved end holding the shaft 105 seated on the open journal. Thus the left hand end of shaft 105 may be pivoted about pin 108 and dissociated from the link 98 and the right hand end of shaft 105 withdrawn from block 104 to allow new bands 10 to he slipped into place. The links 98 and 100' are maintained in the described parallel relationship by the tie rod 109 and link 112 when the bone 20 is thus removed so that it may be readily replaced once new bands 10 have been positioned.

V fiected downwardly as the bands move past the hone 20.

tical in their use in sharpening the blades 10, That is, in the preferred embodiment, above-described, for sharpen-v ing knife bands on both sides of their cutting edges, the

relative disposition of the hones 19 and 20 to the blades 10 is identical save for the fact that th hone 19 is efiective to sharpen one side of the cutting edges while the bone 20 is eifective to'sharpen the other side of the cutting edges.

For simplicity, it will be necessary to describe only the sharpening action of the lower unit 18. One of the advantages of the present invention is to be found in the highly effective manner in which blades having scalloped cutting edges are sharpened both on their high points and their low points. The scalloped cutting edges of the blades 10 is best illustrated in FIG. 8 wherein it can be seen that the blade 10 comprises spaced high points 10a with relieved or low points 10b therebetween.

With this in mind and from FIG. 7, it can be seen that thebeveled surfaces on each side of the cutting edge of the blades do not lie in precisely the same planes, though for purposes of reference in the present invention this discrepancy will be neglected. Thus from FIGS. 2 and 6 it will be seen that the hone 20 is moved into engagement with the bands 10 along a line I which is disposed at substantially the same angle to all of the blades 10, which angle approximates the desired bevel angle 0 (FIG. 7) for the cutting edges of the blades. This relationship is preferably gained by reason of bringing the hone 20 into engagement with the bands 10 along a'line (the line 1) parallel to the line of tangency of the bands with the drum 12 and spaced therefrom a distance such that the 35 twist of the bands 10 forms the angle 0, the bands 10 being further twisted therebeyond into parallel relationship in the slicing zone.

The parallel linkage for moving the hone 20 into engagement with the bands ,10' insures simultaneous engagement with all of the bands (neglecting the existence of high points 1041 mentioned above); The convex cylindrical shape of the abrading or band engaging surface of hone 20 is instrumental in sharpening-both the high points 10a and low points 1012 to preserve the scalloped cutting edges of the knife bands. This end is best appreciated by noting that the hone 20' is moved into engagement with the bands 10 a distance suflicient to contact the low points 1012 (FIG. 7). The high points 10a are then further de The hone 20 is purposely made on a radius sufficiently small so that the hone does not span the high points 10a. Further the natural resilience of the tensioned bands urges the low points 1012 into engagement with the hone 20 With approximately the same force as the high points 10a so that in the sharpening operation approximately the same amount of metal is removed from the high and low points.

Thus'the blades 10 are sharpened and their scalloped cutting edges preserved.

By disposing the units 17 and 18 on opposite sides of the drum .12, it is possible to obtainthe same relationships between the hone 19 and bands 10 for sharpening both sides or the cutting edges of the bands. The shanpening operation requires very little time because of the high speed at which the bands are moving. The removable handles 58 and 116 (FIGS. 1 and 2), (a common handle may be used) are simply connected to the parallel linkages and oscillated a few times to obtain the necessary sharpening or dressing of the cutting edges of the bands 10.

While the present disclosure is based on manual operation of the hones 19 and 20, it is recognized that certain advantages could be obtained by employing automatic or semi-automatic means for bringing these hones into and out of sharpening engagement with the knife bands. 'Thus, for example, an electric motor drive could readily be provided to swing the parallel linkage for each hone in the same manner as the described hand operation. An actuating switch for this electric drive would be mounted for readyaccessibility and convenience on the exterior of the slicing machine or at any remote point desired. Preferably means would be provided for limiting operation of the electric drive to a predetermined time which would I be sufficient for the blades to be sharpened without excessive removal bf material This end could be attained by using a time limit switch which would energize the electric drive for the honors for the desired length of time and then automatically open to deenergize the circuit for the electric drive. Such an arrangement would have the ad- .vantage of further eliminating the human factor in the sharpening of endless knife bands and thus insure uniform sharpening of the blades at all times,

Having thus described-the invention What is claimed as novel and desired to be secured by Letters Patent of the United States is a comprising a cylindrical honingmem ber dis-posed adjacent-one of said drums and spanning one run of said 1 bands to one side thereof, the axis of said cylindrical member being disposed parallel tothe axis of said adjacent drum, means for moving said'honing member into and out of simultaneous engagement with the bevelled surface 1 of the cutting edge of each moving'band, and means res ponsive to said moving means for rotating said honing member about its axis to insure even wear of the cylindrical surface thereof. 7

2. Apparatus for sharpening a plurality of moving knife bandstrained arounda pair of spaced rotating drums and twisted into parallel relationship to provide a slicing zone intermediate said drum-s, saidapparatus comprising i of the bands with said one drum a distance at'which the I bands are twisted to a predetermined'angle with respect to said honing surfacewhich angle approximates the desired bevel angle of the cutting edges of the bands whereby said ,tensioned bandswill be engaged by said honing surface as they are displaced to an angular relationship therewith more precisely equal to the desired beveled angle, and means for. rotating the honing member in response to movement of the parallel linkage means in order to assure even wear of the cylindrical surface of the honing member. j

4. Apparatus as in claim 3 wherein a removable handle projecting outwardly of said bands is provided for actuating the parallel linkage. arrangement and wherein further there is provided spring means effective upon said parallel linkage for maintaining the honing member out of engagement with said bands. 7

5. Apparatus for sharpening both sides of a plurality of moving knife bands trained in loops around a pair of spaced rotating drums and twisted into a parallel relationship to provide a slicing zone intermediate said drums, said apparatus comprising a firstunit including a cylindrical honing-member disposed exteriorly of said loop adjacent onetof said drums and spanning a run of said bands, said member having abrading surface portions disposed in spaced opposed relation to said bands, parallel linkage means for supporting and moving saidrhoning member towards and into engagement with said bands with' the abrading, surface portions thereof engaging the beveled surface on one side of the cutting edge of each moving band and a second sharpening unit including a second cylindrical honing member disposed interiorly of an elongated cylindrical honing member spannin g one run of the bands adjacent one of said drums and means for v moving said honing member into and out of simultaneous 1 engagement with all of said movingbands along a line disposed at susbtantially thesame angle to all of the bands 1 and spaced from the line of t-angency of the runof bands with the adjacent drum a distance such that the bands are disposed relative tosaid line at approximately the desired said loops adjacent one of said drums and spanning a run of said bands, said second member having abrading surface portions disposed in spaced opposed relation to said 7 bands and parallel linkage means for supporting and moving said second honingmember towards and into engagement with said bands with the abrading surface portions thereof engaging the beveled surface of the other side of bevel angle for the cutting edges of the bands, the means i for moving said honing member comprising a parallel 'link-.

age arrangement having pivotal connections with the ends brought into and out of engagement with the bands and -in a direction having components bothtransversely and longitudinally of the axis of the adjacent paratus comprising a honing member including a shaft mounted adjacent one of said drums with its axis parallel to the axis of said one drum and. having a cylindrical hon- 'ing surface formed coaxially of the axis of said shaft'and disposed in spaced opposing relation with one run of said bands, means including a manuallyoperableparallel link- 1 age for moving said honing member, and particularly the of the honing member whereby the honing member is e provide a slicing zone intermediate said drums, said'apthe cutting edge of'each moving 'band,; at least one end a of the second honing member being detachably secured to the parallel linkage means therefor.

means of the second unit'includes a tie rod disposed outlelism.

1 References Cited in the file of this patent 7 UNITED STATES PATENTS 2,537,512 ,Crissey a Ian. 9, 1951 2,768,486 Jones et al. Oct. 30, 1956 1,786,314 Simmons Mar.t26, 1957 2,841,932 Tammen et al. July 8, 1958 2,851,833 1 Hansen Sept. 16, 1958 2,851,834 Hansen Sept. 16, 1958 2,961,809 Hansen Nov. 29, 1960 2,997,823 Irvin Aug. 29, 1961 Hansen Aug. 29, 1961 6. Apparatus as in claim, 5 wherein the parallel linkage V 

